This article supersedes TSB 04-18-4 to update the vehicle model years and Service Procedure.

ISSUE:

Some 2004-2006 F-Super Duty and 2004-2005 Excursion vehicles built after 9/29/2003 with a 6.0L engine may exhibit a turbo-induced exhaust moan/drone between 1500-2000 RPM.

ACTION:

Install a turbocharger bracket A-brace. For vehicles built before 1/17/2005, if the noise is still at an unacceptable level after installing the A-brace, install a revised turbocharger pedestal mounting bracket and neutralize the exhaust system.

If vehicle was built before 1/17/2005, test drive the vehicle and verify if the noise was eliminated or reduced. If the noise is still unacceptable, follow Exhaust Neutralization And Turbochager Pedestal Mounting Bracket Installation procedure. Vehicles built on/after this date already have the updated turbocharger pedestal mounting bracket.

Re-evaluate for exhaust/turbo moan. If condition is corrected return the vehicle to customer. If not corrected, replace the turbocharger pedestal mounting bracket with service Part Number 5C3Z-6N639-AA, following Workshop Manual Section 303-04D (Fuel Charging and Controls – Turbocharger). Perform the following Neutralization Procedure before performing final torque procedure of pedestal to block and reinstalling/refastening turbocharger.

NEUTRALIZATION PROCEDURE – MOUNTING BRACKET INSTALLATION

NOTE:

PROPER ASSEMBLY AND TORQUE SEQUENCE OF THE LHS TURBO Y-PIPE (6K854) AND RIGHT HAND SIDE (RHS) STRAIGHT-PIPE (6K854) CONNECTIONS, TO TURBO, EGR COOLER, AND EXHAUST MANIFOLDS, IS CRITICAL TO ENSURE THE DURABILITY OF THE EXHAUST PIPE FLEX BELLOWS, AND MINIMIZE TURBO INDUCED EXHAUST MOAN/DRONE NOISE.

Check for good alignment and fit of the lower LHS Y-pipe and RHS straight-pipe flanges at the mating exhaust manifold outlets. Secure the LHS Y-pipe and RHS straight-pipe to the exhaust manifold outlets using M8 bolts (two (2) per side). Using hand tools snug fasteners evenly to position the pipe flanges square to the pipe and parallel to the exhaust manifold flanges. There should be an equal gap spacing between the pipe flange and exhaust manifold flange at both the top and bottom bolts (Figure 1).